you just need normal conquest pvp gear from pvp vendor if you already bought those you can go to zereth mortis and theres catalyst which lets you convert your current gear into tier sets head/chest/legs cost 1500 & shoulders/hands 1250 cosmic flux
You can use normal conquest gear and convert it in tier set, you will still be able to upgrade it normally through pvp.
You can also convert pve pieces into set and upgrade them like you would with pve pieces, if you for example find m+ easier you can get full set from there, it has same stats, only ilevel may differ